Improved diagnosis and treatment of persons with movement deficits caused bymusculoskeletal or neurological etiologies partly depends on our ability to assess musculotendinous function. The project's goal is to apply PC MRI to assess muscle and tendon and bone motion function in patients with stroke, spinal cord/nerve injuries, muscular dystrophy and surgical reconstruction. Methods This project's specific aims to date were to develop acquisition and analysis methods for multidimensional velocity measurements of muscle motion using PC MRI techniques. These were refined and validated with in vitro experiments for subsequent application to in vivo experiments. Motion phantoms were used to quantify the accuracy of phase contrast measurements of spatial trajectories, rigid rotation and translation of bone, and muscle contraction. To characterize muscle contraction and myotendinous strain velocity encoded image sets were used to separate components of deformation: translation, rotation, and deformation. Advanced acquisition techniques were developed by transducing the instantaneous position of the limb throughout movement to produce dynamic images with dramatically shortened acquisition times and enable much broader application of these methods to clinical problems. Experimental apparatuses were constructed to allow acquisition of velocity maps for systems of physiologic muscle motion in the upper and lower limbs. This required the development of integral surface coil holders, position transducers and force ergometer. We successfully tested the use of the holder and the Hiemholtz coupled coils for the imaging of a phantom, lower leg and knee. Results showed that coupling of the coils requires careful optimization of a spacing and orientation to obtain the msot homogeneous field. Results and Discussion The success of this work will lead to a readily transportable, clinically useful, noninvasive, and accurate technique for evaluating musculoskeletal motion in three dimensional and improved surgical and rehabilitative treatment of patients with impaired muscle function.